Process for the artificial creation of accumulations of subterranean courses of water



Sept. 2, 1947. DE vn- 2,4Z6,730

PROCESS FoR THE ARTIFICIAL CREATION OF ACCUMULATIONS OF ,SUBTERRANEANCOURSES OF WATER Filed Sept. 11, 1945 INVENTOR ALBERTO DE VITA BY MMAGENT Patented Sept. 2, 1947 PROCESS FOR THE ARTIFICIAL CREATION OFACCUMULATIONS OF SUBTERRANEAN GOURSES'OF WATER Alberto De Vita, BuenosAires, Argentina ApplicationSeptember 11, 1945, Serial No. 615,575Iii-Argentina February 26, 1945 6 Claims.

1 This invention relates to a process for the artificial creation ofaccumulations of subterranean courses of chemically potable water inregions where this is lacking. This process has for its object theimprovement of extensive regions in which the development of animal andvegetable life, as well as human progress, is hampered by theinsufficiency of chemically potable. water.

The process object of this invention takes into account the two typicalaspects of the abovementioned insufficiency, that is: the lack ofsuperficial water, together with the unfitness of subterranean watersdue to-their. excess of minerals in solution,.and the non-existence ofwaterbearing strata at economically exploitable depths.

The process characterized by this. invention is essentially based on theutilization ofrain water towards the following ends:

(a) The creation of pluvial accumulations r subterranean water courses,floating on salt liquid strata.

(b) Improvement in the. chemical characteristics (hardness, salinity,fiuor content, arsenic, vanadium and other toxic substances) of certainsubsoil waters.

(0) The formation of waterbearing strata at economically accessibledepths in places where the existing waters are far removed from thesurface.

The means adopted to date to lessen the damages arising from theaforementioned insufficiency and defective water, are limited to theinstallation of aqueducts and, where this is not possible, to theconstruction of covered receptacles: (cisterns, water-tanks) oruncovered ones: (dams, basins, containers, etc.) meant for the storageof rain water.

In most cases these means fulfill the requirements only relatively forthe following reasons:

(a) The reduced capacity of the receptacles limits the quantities ofwater available.

(b) The decomposition and contamination to which water stored in saidmanner is subject, do not make its use recommendable.

(c) The high volume reduction of the liquid contained in the uncoveredreceptacles (due to evaporation), proportionally increases the mineralcontent of the water, thus making it unfit for human consumption;furthermore, the saline precipitate formed by concentration of the waterafiects the efiiciency of its containers.

(d) The accumulationof insects caused by the presence of stagnant wateron the surface isunwholesome for the respective localities, especiallythose exposed to malaria.

As a means of minimizing the above-men'- tioned drawbacks, in certaincases the volume of the subterranean water'bearing strata was increasedby conducting the river and stream waters into said courses; but this isonly one instance of the usual procedures for obtaining water, as inreality theseare not regions which are devoid of sweet water.

In other cases, the farmers contrive to make the quality of the subsoilwater temporarily usable. by mixing it with rain water, which is made toflow into small containers built near to the wells.

The entirely rudimentary nature of theselatter constructions, and thefact that they never take into account such basic factors as. thetechnical characteristics of the land in its different levels, and theexploitation system of the wells, reduces their relative efficiency tomore or less brief periods of time, after which the subterranean coursebecomes obstructed with particles borne along by the muddy watersincorporated therein, and the well becomes useless; or, on the contrary,the impermeab-ility of the containers floors causes the stored liquid,instead of penetrating into the subsoil, to disappear entirely due toevaporation.

The process characterized by the present invention differs substantiallyfrom the above-mentioned (which, summarily, comprise all the knownprocesses), because, although it utilizes theproduct of rainfalls, itdoes so in a completely new manner, which is strictly related to thegranular and structural characteristics of the subsoil, to theprinciples of physics embodied in the laws of hydrostatics, and to thepossibilities envisaged b said characteristics and principles, in orderto bring about the creation of artificial courses or subterraneanwaterbearing strata, or rather, the improvement in quality of thealready existing water courses.

In fact, the object is todetermine-with the help of means and knowledgesupplied by hydrogeology and geophysics-the exact nature andcharacteristics of that portion of strata and layers which is to be usedfor the creation of reservoirs or receptacles for atmospheric waters.and, based on this and on the possibility of making this reserve waterflow into certain parts of the land, to be able to foresee:

(a) The physical characteristics and quantity of liquid which in theshortest possible time and withoutaltering or possibly improving thesubsoil capacity, may be stored in the portions being studied.

(1)) The distribution in the subsoil of the liquid conveyed as Well asof the existing Water.

The quality and quantity of water that can be recovered and the mostadequate system for its extraction.

In those cases where the subsoil is permeated by salty waters, theabove-mentioned process contemplates the creation of sweet wateraccumulations floating on the salty ones, in a similar manner to whattakes place naturally in the islands formed by dunes. This has beenpointed out and studied in 1887 and 1901 by Radon Chijben and Herzberg,respectively, both engineers, in accordance with that principle ofphysical science which says: The height reached by two nonmixableliquids of different density in communicating glasses is inverselyproportional to their respective densities.

The latter author mentioned investigated the details of said phenomenon,especially in the Norderney Island (Oriental Frisia), and establishedthat: The depth at which displacement of salt water takes place belowmean sea level can be determined by multiplying the relation between thedensity of the sweet water and the difference between the density of thesea water and that of the sweet water, by the height of this latterabove sea level.

Figure 1 illustrates the observations of said author, the meaning of theletters being as follows:

D, space occupied by sweet water.

S, space occupied by salt water.

M, sea surface.

L/f, phreatic surface of sweet water.

L/ m, mean sea level.

t, height of sweet water above mean sea, level.

It, depth at which displacement of salt water took place below mean sealevel.

I-I, maximum depth of sweet water.

Supposing the density of sea Water is 1.027, and that of sweet water is1, and that the height 15 of this'latter above sea level is 1.80 then:

that is: V

h=37 1.80,:6650 meters This figure was proven to be correct in theaforementioned island by means of borings. Some of these reached a depthof 98 m., and the sweet water limit was found at the 60 m. mark, beneathwhich the zone of dispersion was encountered, where salt water waspresent for a width of approximately 5 m. 1 v

Evidently, the simplicity of this phenomenon in dune islands whosesubsoil may be considered homogeneous, at least up to considerabledepths, becomes a complicated matter to study in continental regionswhere the subsoil is greatly varied and frequently alternated byimpermeable strata.

Maybe this is one of the principal reasons for there being littleevidence of similar cases which, due to the aforementioned heterogeneouscharacteristics, often appear in certain regions, but are not soapparent.

In fact, in most cases the roof above the salt waters is a region'ofcementation, formed by a practically impermeable layer.

This causes the atmospheric waters absorbedby the ground, instead ofresting directly above the salt water and inflecting its surface(similar to what occurs in the abovementiond islands), to

water courses and, thus the displacement of the. liquid contained insame, during penetration of called phreatic layer, which, often beingvery shalf low, is of doubtful use.

In these cases, and in general in all those of a similarlnature, theprocess object of this invention foresees the direct conductiongof rainwater to the salt water layers, aided by the pressure maintained bywater in a filtering column, the height of which is equivalent 'to the,distance be tween the surface of the ground and the roof of salt water.i

Sketched in Figure 2 are some details of the basic constructionsentailed by said process, the indications being as follows:

I, an adduction well system for conducting atmospheric waters to thephreatic layers.

2, an annular water settling ditch for sedimen tation of the waterbefore its entrance into the adduction well.

3, an annular filter formed by sand, gravel and stone of difierentgradings, for the purpose of fil-' tering water before its entrance intothe settling ditch.

4, a series of straight filtering obstacles, formed like the previousone, for the first filtering of the water, before it reachestheadduction reservoir, in which well I is situated. p 7

5, an embankment provided with drains for the purpose of containing thewater that flows into the adduction reservoir. V

5, a series of bore wells, filled with gravel, to facilitate the escapeof air from the subterranean atmospheric water through well I. v I

I, means of extraction to be installed in well I, for the utilization ofwater conducted in the subsoil.

8, curb of well II 9, curb-apron of said well. 7

I 0, annular holding wall. a

I I, air passages or breathing holes.

I2, crevices for the access of water to well I.

I3, revetment or lining of the extraction well.

I4, revetment or lining of the adduction well.

I5, filter of the'adduction well, formed by sand,

. gravel and stones of different grading.

strata (cementation region).

I6, bottom filter of extraction well for the waters to be used; formedby sand, gravel and stones of different grading. v

I'I, roof of the salt water layer and impermeable I8, hypotheticalsection'of the surface inflection of the salt water, produced inahomogeneous layer, by the penetration of sweet water through well I,when the level of said well is at the height indicated by No. t9, andthe revetment of the adduction well closes perfectly with impermeablelayer I'I. 7' i I V 20, hypothetical section of. the surface limitbetween the salt and sweet water when this latter overlaps thecementation region, as indicated by line ZI, and escapes through thecontact between the adduction well revetment and the imperme-- ablestrata II. a s

22, space occupied by'sweet water and,. r h

23, space occupied by salt water when both liq uids are balanced. a

Figure 3 is a birds-eye view showing distribu-, tion of the worksfreferred to in Figure 2.

It is worth mentioning'that the section of the separation surfacebetween the saltand the sweet water will change, widening'or lesseningwith the level of the sweet water in the adduction well,

while its shape will alter considerably when the thickness of the saltwater layer is inferior to that required.

Although the works specified in Figure 2 answer the .basic needs of thepresent process (where cases of salt water are concerned), they may varyas to size, quantity and distribution, according to the subsoilcharacteristics, availability of atmospheric water and the requirementsof each case.

When improvement of the chemical characteristics of subterranean watersis desired (hardness, salinity, fiuor content, arsenic, vanadium andother toxic substances), the process referred to may be modified alongsimilar lines to those specified for salt Water.

In such cases the improvement will be made by dilution, and instead ofobtaining, as in the previous cases a space occupied only by atmosphericwater, there will be a sp 0eproportional to the quantity of wateradduced-occupied by the water from the natural layer diluted with theatmospheric water.

Figure 4 shows the steps of the process in those cases where it isnecessary to create subterranean waterbearing strata at economicallyaccessible depths. In said figure references are as follows: I is theadduction well, which in these cases can be built simply like anordinary well, filled in with filtering material I5, but alwayssurrounded by sedimentation ditches 2, filters 3 and 4 and embankment 5,the shapes, quantity, type and position of which may vary, as in thecases previously mentioned.

This well will reach a permeable layer 24 to which it will conduct theatmospheric water, which will drain above the impermeable layer 25, andmay be captured downstream at an adequate distance by the extractionwell 26, which will reach the impermeable layer and penetrate samethrough receiving Wel 27.

Means of extraction 1 will carry the captured Water to the surface.

By this process it will be possible in some cases to create watersources 28 when the impermeable layer 25, at some distance downstreamfrom adduction well I, reaches or meets the surface.

When permeability of the subsoil is not very great and the layer towhich water is conducted is of suflicient depth, once said layer issaturated, it will be easy to obtain volumes of water which, if notabundant, at least may be considered as permanent.

In those cases where said permeability is excessive it can be lessenedby conveniently reducing the filtering of waters conducted to thesubsoil.

Obviously, several modifications as to construction and specificationmay be introduced, keeping within the lines of this invention, so longas the variations are within the scope of a fair interpretation of theclaims.

I claim:

1. A system for the artificial creation of accumulations of subterraneancourses of water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable strata containing salt water, said permeablestrata being superimposed on the impermeable layers, at least onefiltering element and at least one containing element surrounding theaforesaid well and forming a settling ditch provided with thecorresponding drains, this arrangement being adapted to store water ofatmospheric origin in the phreatic layers by displacement of the saltwater contained in said phreatic layers.

2. A system forthe artificial creation of accumulations of subterraneancourses of water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable. strata containing salt water, said permeablestrata being superimposed on the impermeable layers, at least onefiltering element and at least one containing element surrounding theaforesaid well and forming a settling ditch provided with thecorresponding drains, and at least one additional well for the escape ofair contained in the subsoil, this arrangement being adapted to storewater of atmospheric origin in the phreatic layers by displacement ofthe salt water contained in said phreatic layers.

3. A system for the artificial creation of accumulations of subterraneancourses of water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable strata containing salt water, said permeablestrata being superimposed on the impermeable layers, at least onefiltering element and at least one containing element surrounding theaforesaid well and forming a settling ditch provided with thecorresponding drains, and at least one liquid extraction means provideddownstream from the adduction well, this arrangement being adapted torecover water of atmospheric origin accumulated in the phreatic layersby displacement of the salt Water contained in said phreatic layers.

4. A system for the artificial creation of accumulations of subterraneancourses of water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable strata containing salt water, said permeablestrata ibeing superimposed on the impermeable layers, at least onefiltering element and at least one containing element surrounding theaforesaid well and forming a settling ditch provided with thecorresponding drains, and at least one extraction well provideddownstream from the adduction well, this arrangement being adapted torecover water of atmospheric origin accumulated in the phreatic layersby displacement of the salt Water contained in said phreatic layers.

5. A system for the artificial creation of accumulations of subterraneancourses of water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable strata containing salt water, said permeablestrata being superimposed on the impermeable layers, at least onefiltering element and at least one containing element surrounding theaforesaid well and forming a settling ditch provided with thecorresponding drains, at least one additional well for the escape of aircontained in the subsoil, and at least one liquid extraction meansprovided downstream from the adduction well, this arrangement beingadapted to store water of atmospheric origin in the phreatic layers bydisplacement of the salt water contained in said phreatio layers.

6. A system for the artificial creation of accumulations of subterraneancourses of Water of atmospheric origin and chemically potable,comprising an adduction well extending to and reaching the phreaticlayers or the permeable strata containing chemically non-potable waterdue to the excess of minerals, hardness or toxic substances, saidpermeable strata being superimposed on the impermeable layers, at leastone filtering element and at least one containing element surroundingthe aforesaid well and forming 7 8 a settling ditch provided with thecorresponding drains,. this arrangement being adapted to store UNITEDSTATES PATENTS 7 water of atmospheric origin in the phreatic lay- Numbere Date 61's by dilution of the chemically non-potable 415,543 Light Nov.19, 1889 water contained in said phreatic layers with rain 5 5 Sooy June8, 1915 water. 1,7 1,308 Enderson Apr. 30, 1929 REFERENCES CITED The'following references are of record in the 16 file of this patent:

ALBERTO DE VITA 2,375,865 Nebolsine May 15, 1945

